Clamp Meter

ABSTRACT

A clamp meter is revealed. The clamp includes a pair of jaws disposed on a main body. The main body is arranged with a display panel and a plurality of buttons. The two jaws can be opened or closed by manual operation to get data of an object users intend to measure. The data is transferred to the main body and shown on the display panel. Users can switch to the electrical parameter they need by pressing the buttons. The clamp meter features on a plurality of indicator lights disposed on the jaws. Users can obtain current data directly by observing the indicator lights.

NOTICE OF COPYRIGHT

A portion of the disclosure of this patent document contains materialwhich is subject to copyright protection. The copyright owner has noobjection to any reproduction by anyone of the patent disclosure, as itappears in the United States Patent and Trademark Office patent files orrecords, but otherwise reserves all copyright rights whatsoever.

BACKGROUND OF THE PRESENT INVENTION Field of Invention

The present invention relates to a test meter, especially to a clampmeter that measures electrical parameters such as current, voltage, etc.of wires.

Description of Related Arts

Generally, a clamp meter is a test meter with a pair of jaws and usedfor measuring current on wires/cables. Nowadays the clamp meter withmore functions is able to measure more electrical parameters such asvoltage. A processor in the clamp meter can be used to test voltage.Some clamp meters even have the same basic functions as the digitalmultimeter (DMM). Refer to U.S. Pat. No. 6,975,104B2, a clamp meter withdual displays is revealed. The current/voltage signal obtained is sentto the displays to be read by users. However, users are unable to getdata of electrical parameters once the display is out of order.Moreover, users are unable to learn whether an object to be tested iscarrying electric current immediately. Thus users' safety remains aconcern.

SUMMARY OF THE PRESENT INVENTION

Therefore it is a primary object of the present invention to provide aclamp meter that reaches a higher safety with a plurality indicatorlights on jaws thereof. Besides reading on the display, the indicatorlights show users that whether an object measured is carrying electriccurrent and users can learn the magnitude/range of the current directly.Thus users can get electrical parameters such as current, voltage, etcimmediately and injuries from contact with live parts can also beavoided.

In order to achieve the above object, a clamp meter according to thepresent invention includes a main body a first jaw and a second jaw. Aprocessor is built in the main body and used for processing variouskinds of electrical parameters such as alternative current (AC) voltage,direct current (DC) voltage, resistance, current, etc being measured.The main body is also arranged with a display panel and a plurality ofbuttons, usually on a front surface thereof.

The first jaw and the second jaw are both pivotally connected to a topend of the main body and used for detection of current and voltage. Thefirst jaw and the second jaw are set correspondingly, able to be closedor opened. Each jaw includes a first end and a second end extended fromthe first end. A first current transformer and a second currenttransformer are set between the two ends of the first jaw and the twoends of the second jaw respectively. Each current transformer is formedby a plurality of silicon steel sheets stacked and each silicon steelsheet is covered with an insulating coating. After sensingelectromagnetic signals related to current, voltage or resistance, asensor connected to the first and the second current transformers getssignals. A test space is formed between the two second ends of the firstand the second jaws closed toward each other. The test space is used fordetecting flowing of the current. A plurality of indicator lights isdisposed on a surface between the first end and the second end andarranged along the jaws. Circuit of the sensor is connected to theindicator lights and also connected to the processor of the main body.An object detected is set within the test space and then the first andthe second current transformers detect the object, generate signals andtransfer the signals to the sensor. Next the sensor sends the signals tothe indicator lights and the processor of the main body respectively.The indicator lights are turned on according to the signals received andthe magnitude of the current is represented by the number of theindicator lights turned on. The precise data of the current and thevoltage is also shown in the display panel of the main body.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objects can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein:

FIG. 1 is a perspective view of an embodiment according to the presentinvention;

FIG. 2 is an explosive view of an embodiment according to the presentinvention;

FIG. 3 is an enlarged explosive view of a first jaw and a second jaw ofan embodiment according to the present invention;

FIG. 4 is a longitudinal sectional view of an embodiment according tothe present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Refer to FIG. 1, a clamp meter of the present invention includes a mainbody 1, a first jaw 2 a and a second jaw 2 b. The main body 1 is builtin with a processor (not shown in figure) for processing and measuringvarious kinds of electrical parameters including alternative current(AC) voltage, direct current (DC) voltage, resistance, current, etc. Themain body 1 consists of a display panel 11 disposed on a front surfacethereof and a plurality of buttons 12, 13, 14. The button 13 is used forcontrol or switch of signal processed such as processing of currentsignals, voltage signals, resistance signals, etc. The button 12 is usedas an on/off switch and for process switching.

The first jaw 2 a and the second jaw 2 b both are disposed on andextended from a top end of the main body 1, as shown in FIG. 2 and FIG.3. The first jaw 2 a and the second jaw 2 b are disposed correspondinglyto each other, able be opened or closed. A test space 25 is formed whenthe first jaw 2 a and the second jaw 2 b are closed toward each other.The button 14 is formed by extension of a first end 21 of the first jaw2 a. The opening and closing of the first jaw 2 a and the second jaw 2 bare controlled by the button 14. In this embodiment, the first jaw 2 aand the second jaw 2 b are formed by connection of first housings 22 a1, 22 a 2 with second housings 22 b 1, 22 b 2 respectively. The firsthousing 22 a 1/22 a 2 is disposed with a slot 23 a 1/23 a 2. Each of thefirst jaw 2 a and the second jaw 2 b includes the first end 21 and asecond end 22 extended from the first end 21. The slot 23 a 1 of thefirst housing 22 a 1 is mounted with a first current transformer 24 awhile the slot 23 a 2 of the first housing 22 a 2 is mounted with asecond current transformer 24 b, as shown in FIG. 3 and FIG. 4. Then thesecond housings 22 b 1, 22 b 2 and the first housings 22 a 1, 22 a 2 areconnected correspondingly to form the first jaw 2 a and the second jaw 2b. The first end 21 of the first jaw 2 a and the second end 22 of thesecond jaw 2 b are disposed with a non-conductive barrier 28 a and anon-conductive barrier 28 b respectively. Thereby the first end 21 andthe second end 22 are separated from each other by the non-conductivebarriers 28 a, 28 b and a contact surface therebetween is non-conductivewhen the first jaw 2 a and the second jaw 2 b are closed. Anelectromagnetic field formed by current through the object within thetest space 25 between the first jaw 2 a and the second jaw 2 b isdetected by the first current transformer 24 a and the second currenttransformer 24 b and a corresponding electromagnetic signal isgenerated.

A surface of the first jaw 2 a and a surface of the second jaw 2 b aredisposed with a plurality of indicator lights 26 respectively. Theindicator lights 26 are arranged along the first jaw 2 a and the secondjaw 2 b and each indicator light 26 is labeled with the number ofcurrent therebeside. The circuit of the indicator lights 26 is connectedto the first current transformer 24 a and the second current transformer24 b. The power source of the indicator lights 26 is from a circuit 28connected to a power supply of the main body 1. An object detected isplaced into the test space 25. An electromagnetic field formed bycurrent through the object within the test space 25 is detected by thefirst current transformer 24 a and the second current transformer 24 band a corresponding electromagnetic signal is generated. Then a sensor(not shown in the figure) connected to the first current transformer 24a and the second current transformer 24 b gets the electromagneticsignal. Next a certain number of indicator lights 26 are turned onaccording to the electromagnetic signal measured. The number of theindicator lights 26 turned on is proportional to the magnitude of thesignal obtained. In other words, the number of the indicator lights 26on the first jaw 2 a and the second jaw 2 b turned on is increased ordecreased according to the signal obtained when the first jaw 2 a andthe second jaw 2 b detect the voltage or the current. The indicatorlights 26 can warn and remind the users clearly.

After the electromagnetic signal being obtained by the sensor connectedto the first current transformer 24 a and the second current transformer24 b, the sensor sends the signal measured to the indicator lights 26for lighting the indicator lights 26 directly. The sensor also sends thesignal measured to the processor (not shown in figures) of the main body1 through another circuit 27 to display detailed data of thevoltage/current signals on the display panel 11 of the main body 1.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details, and representative devices shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalent.

What is claimed is:
 1. A clamp meter comprising: a main body having aprocessor that is built-therein and used for detecting and processingvarious kinds of electrical parameters, a display pane; and a pluralityof buttons disposed on a front surface thereof; and a first jaw and asecond jaw, both pivotally connected to a top end of the main body,arranged correspondingly and able to be closed or opened; wherein eachof the first jaw and the second jaw includes a first end and a secondend; a first current transformer and a second current transformer areset between the first end and the second end of the first jaw and thefirst end and the second end of the second jaw respectively; the firsttransformer and the second current transformer are connected to asensor; a test space is formed between the first and the second jawsclosed to each other; an electromagnetic field is detected by the firstcurrent transformer and the second current transformer; the test spaceis used for detecting electromagnetic signals generated by currentflowing through; a plurality of indicator lights is disposed on asurface between the first end and the second end; circuit of the sensorconnected to the first transformer and the second transformer is alsoconnected to both the indicator lights and the processor of the mainbody; wherein an object to be detected is placed within the test spaceand then an electromagnetic field form by current of the object withinthe test space is detected by the first and the second currenttransformers and a corresponding electromagnetic signal is generated;the sensor connected to the first and the second current transformersgets the electromagnetic signal and sends the electromagnetic signal tothe indicator lights and the processor of the main body respectively;wherein the indicator lights on the first jaw and the second jaw areturned on according to the signal received and magnitude of the currentis represented by the number of the indicator lights turned on; theelectromagnetic signal is converted by the processor of the main bodyinto data including current and voltage to be shown on the display panelof the main body.
 2. The device as claimed in claim 1, wherein theindicator lights are arranged along the first jaw and the second jaw;each of the indicator lights is labeled with a number of currenttherebeside.
 3. A clamp meter comprising: a main body having a processorthat is built-therein and used for detecting and processing variouskinds of electrical parameters, a display panel disposed in front of themain body and at least one button for control or switch of theelectrical parameters being processed; and a first jaw and a second jaw,both pivotally connected to a top end of the main body, arrangedcorrespondingly and able to be closed or opened; a test space is formedbetween the first jaw and the second jaw closed to each other; the firstjaw and the second jaw are arranged with a first current transformer anda second current transformer; an electromagnetic field formed by currentthrough an object detected within the test space is detected by thefirst current transformer and the second current transformer and atleast one corresponding electromagnetic signal is generated when thefirst jaw and the second jaw are closed; wherein the electricalparameters includes alternative current (AC) voltage, direct current(DC) voltage, resistance, and current; wherein a plurality of indicatorlights is disposed on a surface of the first jaw and the second jaw andeach of the indicator light is labeled with a number of currenttherebeside; current of the indicator lights is connected to the firsttransformer and the second transformer; thereby the electromagneticfield of the object detected within the test space is detected by thefirst and the second current transformers and the correspondingelectromagnetic signal is generated when the object detected is setwithin the test space; thus a number of the indicator lights are turnedon according to the electromagnetic signal detected after the sensorgets the electromagnetic signal.
 4. The device as claimed in claim 3,wherein the indicator lights get power by circuit connected to a powersource of the main body.
 5. The device as claimed in claim 3, whereinthe sensor sends the signal to the processor of the main body so thatdata of the electrical parameter is shown in the display panel of themain body.